LSJ
later Greek, = ἦ μήν, LXX Ge. 22.17, al., PTeb. 22.13 (ii BC), etc. ; Dor. εἶ μάν IG 5(1).1390.27 (Andania, i BC).
Liddell-Scott-Jones, Greek-English Lexicon (9th ed., 1940)
Pape
nach EM. p. 416.50 = ἦ μήν.
Pape, Griechisch-deutsches Handwörterbuch (3. Aufl., 1914)